I want to get the last 25 elements of a collection in Firebase

Recently I've built a chat app using react + firebase but there's something that doesn't work quite right.

I'm able to send messages and have them stored in the firebase database. Now here's the problem: it only shows the first 25 messages that got stored.

Here's the part of the code that's problematic:

const messagesRef = firestore.collection("messages");
const query = messagesRef.orderBy("createdAt").limit(25);

Is there a way to start at the bottom from the last 25 message? Using "desc" doesn't work either because it displays the data starting from the last message at the top and I want the exact opposite.

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